Manufacture of aluminum chlorid.



aiaaaoaf siding at fYorkf and State of New York, have in- 35. which latter event 50 may QFFKQEQ 'MODUFFIE MOAFEE, OF NEW YORK, N. Y.-

No Drawing.

To all whom it may concern Be it known that I, ALMER MCDUFFIE "McAinii-a citizen of th'e' United States, re-

New York, in the county ofNew vented certain new and useful Improvements in the Manufacture of Aluminum hlorid, of which the following-is a specification.

Thisfinvention relates to manufacture of aluminum chlorid; and it comprises a method of makinganhydrous, active aluminum chlorid from-certain c'oky or sludgy residues formedin the catalytic conversion 15. and refining of petroleum. oils by aluminum chlorid wherein aluminum chlorid is extracted from such residues with water and hydrated aluminum chlorid formed, such hydrated aluminum chloridis decomposed .20v by'heat' to form hydrochloric acid and alumum, and such hydrochloric acid is passed over heated alumina in the presence of carbon to form vapors of'anhydrous aluminum chlorid;- such carbon being advantageously furnished by anothei ortion of untreated residue; all as; more forthaiid as claimed. y i Aluminum chlorid'is advantageously used for the sake of its catalytic properties in a lly hereinafter set number of processes in the manufacture and refining of petroleum products. It may for example be used-to convert crude oil, gas "oil, etc, into gasolene, or gasolene and kerosene; such conversion being total .or partial, .in'

a portion of good gasolene' and a portion of much improved high boiling oil may be'obtained. At lower tem peratures aluminum chlorid may be usedto remove the asphaltic constituents of'lubri- 40 cating oil, diminish the amount of unsaturatedgroups present,.e tc. In all these uses although the aluminum chlorid appears to I act only by reason of its catalytic properties, yet after a time it loses activity. For example, after use in catalyzing oil for a time,

on cooling the oil body, the aluminum chlorid settles out as a sludge. Through repeated use of the sludge on fresh oil, the sludge becomes, moreand more coky until finally it become a. comparatively hard,. fine grained," coky deposit. In this-coky mass the aluminum chlorid appears to be contained as such but it does not have it's-usuaiiproperties. For' instanc e, it has lost much 5 or most oi its-catalytic convertlng proper-- ties as rega'rdbilsyi-t cannot be vaporized;

' such sludge or properties of the tage of the MANUFACTURE or ALUMINUM cHLoBLno,

1915. 1915. Serial No. 11,548.

away by.heating the coky mass to a low red -heat although aluminum chlorid, per 86, vol- 'atilize's freely at 365 F. It may be that the aluminum chlorid is in combination with pitchy-hydrocarbons or it may be that it is merely adsorbed and retained in some man nor bythecarbon. Where the oil with which the aluminum chlorid has been used was, as it should have been, dry, there is relatively-little alumina in these residues;

ey appear to, contain aluminum and chlorin in the correct proportion for aluminum chlorid. The aluminum chlorid may. be released from its state of union or combination in these residues and regained in a. highly active state by heating such coky residues with-a modicum of chlorin (see Patent N 0. 1099096) .7 alittle chlorin serving to release-a relatively, large amount of ac-' tive aluminum chlorid. The present invenaluminumchlorid from these residues. The residues as they come from the oil converting or improving operation can more or less oil;:the amount of this-oil di fering with the particularprocess. If the sludge or coke carrying the aluminum chlorid has been allowed-to cool down in the presence of the'body of'oil, it may contain as high as 40to 50 per cent. of oil. If the oil body-has been separated from the aluminum cliloridsludge or coky mass while hot and coke is well drained and particularly. if--=vacuum draining be used, the

per cent.

'I have found that if I take these residues after removing the oil, or the bulk of it, in any suitable manner, as by extraction, pressing' or combustion, 1 can then extract the aluminum chlorid with a little water to obtainafi concentrated solution of'hydratedaluminuin chlorich Aluminum chloridin the hydrated state does not have x the catalytic anhydrous material but I may use the extractedxhydrated salt'as a raw material for making active anhydrous aluminum chlorid. To do this, I take advani chlorid of breaking up when heated. with: the formation of alumina and hydrochloric acid (HCl)., The alumina, when mixed with "carbon, ('which may be carbon derived; fro'nn a portion" of extracted sludge),"'and treated withhydro'chloric acid vapors at a. hi'gliffteztrr'perafilure','reacts to form anhydrous property of hydrated aluminumi;

amount of" residual oil may be only 4 to 5 I p dried HCl vapors over a portion of alumina from the same or from a previous operation, such alumina of course being used in admixture with carbon and in. a highly heated state. In the presence of carbon the H01 reacts with the hot A1 0 to form A1 01. hydrogen and oxids of carbon. The aluminum chlorid vapors passing from the reaction zone may be condensed in any suitable manner.

In an advantageous embodiment of my invention instead of mixing the alumina from a roasting operation with pure carbon, I use fresh or untreated sludge or coke to furnish the necessary carbon. The carbon of this sludge or coke operates as before while such aluminum chlorid as is contained in the residue is liberated as the carbon disappears and joins that formed by the HCl acting on the alumina. In this manner I am enabled to largely increase my yield of active aluminum chlorid without increasing the expense of operation.-

In using my method I may take the described sludgy or coky residue and first extract the oil. If the residue be rich in oil this may be accomplished in part in a centrifugal; the bulk of the oil being spun off. Heat sufficient to make the oil freely fluid should be employed. Any residual oil in the so treated mass may be burnt off or may be allowed to remain. Or instead of using a centrifugal I may take the residue and extract it with a little gasolene or the like to recover the oil. Or if the residue is comparatively poor in oil, containing, say a to 5 per cent., it may be simply roasted with a limited access of air.

In whatever manner the oil has been removed, the oil-freed residue is next subjected to the action of a small amount of water or of low temperature steam. Alu= minum chlorid being'very deliquescent, a little steam will suflice to form a saturated solution which may be readily extracted. In fact, prior to the extraction of the aluminum chlorid by water, these residues should be carefully guarded against contact with damp air since otherwise the aluminum chlorid will deliquesce rapidly. x

In a practical embodiment of my inven- I tion I may take the oily sludge or coke and place it in any suitable type of centrifugal where it can be treated more or less hot. After the flow of oil has substantially ceased, the material may be removed and burnt or extracted with gasolene liand returned. Or

the material may be ailowed to remain in the centrifugal "without attempting to get rid of the remaining small amount of oil. In either case, I next expose the material in the centrifugal to the action of a limited amount of low temperature, saturated steam or to a fine spray of water; using but little water. The aluminum chlorid in the coky mass hydrates with the formation of a saturated solution which is then expelled by centrifugal action. The'extracted coke or carbon from the centrifugal may be reserved for use in a later operation or may be used for fuel, for making carbon plastics, etc.

In extracting with water or steam in'the centrifugal the solution formed should be as nearly saturated as possible. If wash water is used, it should be separately collected and used for extracting another charge. Much of the economy of the present operation depends on obtaining aluminum chlorid solutions as concentrated as possible. Instead of using a centrifugal, an ordinary suction filter or a filter press may be employed. However, a centrifugal is convenient. The strong solution of aluminum chlorid is next evaporated at as low a temperature as possible. This results, according to circumstances, in a crystalline or a gummy mass. In either event the aluminum chlorid so obtained is next carefully roasted at a slowly increasing temperature. Under the influence of the heat it dehydrates and forms hydrochloric acid vapors. The vapors may be chlorid to remove the waterand give a dry,

or substantially dry, I-ICl gas. This dry ing is not absolutely necessary but it is advantageous since it reduces the amount of deoxidation necessary in the formation of aluminum chlorid in a subsequent operation. Any water vapor which may occur with the hydrochloric acid gas, must also be reduced by carbon in the formation of aluminum chlorid; that is, in making anhydrous aluminum chlorid there must be carbon present sufiicient in amount not ,only to reduce the A1 0 but also any H O which may be present.

Ordinarily I conduct the roasting of one sample to produce HCl and the treatment of a. body of alumina with such HCl simultaneously although the HOl driven off from a given portion of coky residue may be returned into contact with the same alumina. The alumina resulting from the roasting operation is dehydrated as far as possible by. the heat prior to conversion with H01 and carbon.

The dehydrated alumina so formed is next mixed with carbon. The carbon and alumina may be formed to cakesvor briquets with the aid of a little tar, asphalt, pitch or other binder, but the necessity of this of course depends largely, upon the type of apparatus relied upon to act masses temperature to: form and volatilize alumimun chlorid. v

In an advantageous embodiment of this invention in lieu of using coke or carbon in making this mixture to form aluminum aluminum chlorid which it holds is released or other apparatus.

and joins the new aluminum chlorid which is made.

The alumina in admixture with carbon, or with coky or sludgy residues, as the case may be, is next exposed to the action of dry or substantially dry hydrochloric acid vapors coming from aroasting operation. This exposure should be at a low red heat and may be performed in any suitable retort Under the influence of the heat the alumina is reduced, as previously described, and forms aluminum chlorid which volatilizes and passes forward to be condensed. Any moisture present is also reduced to form hydrogen.

Instead of regaining the hydrated aluminum chlorid by evaporation in the manner previously described, the concentrated solution may be treated with a little hydrochloric acid gas. While aluminum chlorid is very soluble in water, and in Weak hydrochloric acid, it is quite insoluble in solualuminum chlorid. But where tions containing a moderate amount of HCl and crystallizes out. method of recovering hydrated aluminum chlorid in a granular crystalline state well adapted for the roasting operation. While the coky or sludgy resldue may be treated with water in bulk, as by placing it in a vat With water, I do not recommend this procedure since the solutions so obtained are not as concentrated, and consequently not as advantageous, as those made in the manner just described.

Where the operation is carefully conduct- 'ed throughout, the amount of hydrochloric acid obtained should be sufiicient to convert the alumina into reactive anhydrous losses of hydrochloric acid occur before they may be supplemented by the addition of hydrochloric acid gas from another source or by an addition of chlorin. This chlorin is best added to the HCl gas transmitted carbon or of alumina and sludgy residue.

In an alternative embodiment of my invention, in lieu of extracting hydrated aluminum chlorid from the residual carbon may simply allow it to remain, the carbon 0 the residue itself acting as a reducing This is a convenient' any stage .ess of making over the admixture of alumina and posing to the agent. In so. doing,-I-may,- forexample, steam or moisten a portion of the coky residue. This hydrates the aluminum chlorid but does. not remove it from the, carbon. On now roasting, HCl is formed/as before and as the temperature increases the H01 new acts on the alumina in the presence of the carbon of the coky residue to form anhydrous chlorid. There is ordinarily sufficient carbon present not only to reduce the alumina but also a substantial amount of H 0. In this operation however the amount of moisture or steam used is ordinarily restricted to the. amount merely suflicient tobreak up the aluminum chlorid.

1 The HCl formed in roasting may be removed and dehydrated and then returned for the operation at high heat or it may be allowed to remain in the chamber. For example, a charge of coky residue in a retort may be treated with a little steam and then the heat progressively raised through the roasting temperature to the temperature necessary to form anhydrous aluminum chlorid.

What I claim is 1. In the treatment of coky or sludgy residuesarising from the treatment of oil with anhydrous aluminum chlorid, the

process which comprises treating such residues to obtain hydrated aluminum chlorid, breaking up the hydrated aluminum chlorid by heat to, form hydrochloric acid and alumina, mixing the alumina with carbon and submitting the mixture to the action of hydrochloric acid gas at a high temperature.

2. In the treatment of coky or sludgy residues arising from the treatment of oil with anhydrous aluminum chlorid, the process of making anhydrous active aluminum chlorid from sludgy or coky residues containing the same, which comprises treating such residues to obtain hydrated aluminum chlorid, breaking up the hydrated aluminum chlorid by heat to form hydrochloric acid and alumina, mixing the alumina with carbon in the form of untreated coky residue and submitting the mixture to the action of hydrochloric acid gas at a high temperature.

3. In the treatment of coky or sludgy residues arising from the treatment of oil with anhydrous aluminum chlorid, theprocanhydrous active aluminum chlorid from sludgy or coky residues containing the same, which comprises extract ing oil from such residues, treating extract ed residue with a limited amount of moisture to produce a concentrated solution of hydrated aluminum chlorid, breaking up the hydrated aluminum chlorid by heat to produce hydrochloric acid aml alumina, ad-

mixing the alumina with carbon and exaction of hydrochloric acid vapors Z residues arising from the treatment of oil with anhydrous aluminum chlorid, the process of making anhydrous active aluminum chlorid from sludgy or coky residues containing'the same which comprises extracting oilrfroln such residues, treating the extract'ed: residue with a limited amount of moisture to produce a concentrated solution of hydrated aluminum chlorid, breaking up the hydrated aluminum chlorid by heat to produce hydrochloric acidand alumina, admixing the alumina with fresh untreated residues.

5. In the treatment of coky or sludgy residues arising'from the treatment of oil with anhydrous aluminum chlorid, the process which comprises hydrating such aluminum chlorid, roasting to A1 0 and heating the A1 0 with HCl and carbon at a high temperature and submitting the mixture to the action of hydrochloric acid at a high temperature.

In testimony whereof, I aifix my signa ture in the presence of two subscribing witnesses.

ALMER MCDUFFIE MGAFEE.

Witnesses: K. P. MoELRoY,

GEORGE G. McDANIeL.

form 1101 and 1 

